Method for conducting sonochemical reactions and processes

ABSTRACT

Described herein are method for conducting sonochemical reactions and processes in a liquid. The liquid is passed through a device that generates a liquid jet containing cavitation bubbles and collides the liquid jet with an impact body or other liquid jet to force the collapse of the cavitation bubbles at a select compressive stagnation pressure. The compressive stagnation pressure of the liquid is between 50 and 99 percent of the static pressure of the liquid upon entry of a constriction that generates the liquid jet containing cavitation bubbles.

This application claims the benefit of U.S. provisional application Ser.No. 62/013,785 filed Jun. 18, 2014, the contents of which areincorporated herein in their entirety by reference.

FIELD

The invention relates to methods for conducting sonochemical reactionsand processes in aqueous and non-aqueous liquids, and more particularly,to methods that utilize hydrodynamic cavitation effects for conductingthe sonochemical reactions and processes. The method and processes ofthe present invention are effective and useful in the fields ofchemistry, electronic materials, petroleum chemistry, biochemistry,water treatment, food, agriculture, medication, and the pharmaceuticalindustry.

BACKGROUND

Sonochemistry involves the application of ultrasound energy to carry outchemical reactions and processes. The mechanism causing sonochemicaleffects in liquids is the phenomenon of ultrasonic cavitation. There aremany chemical reactions that are influenced by ultrasonic cavitation andthat influence can alter the speed and yield of finished products.

There also exists a great quantity of chemical reactions thatbeneficially proceed under the influence of ultrasonic cavitation.Similar reactions may be accomplished in aqueous, as well asnon-aqueous, liquids. Chemical action can occur in the cavitation bubblecollapse when there is significant compression heating of the vapor andgas. (Timothy J. Mason, “Advances in Sonochemistry”, Volume 3. 1993. 292pp., JAI Press Inc.). As the cavitation bubble accelerates through thecollapse, no heat is lost through the bubble interface in the finalcollapsed stage. Though no heat is lost with respect to the amountstored (adiabatic process), there is vigorous heat flux for a briefinstant and a thin thermal boundary layer forms near the bubbleinterface. Experimental results have shown that these bubbles havetemperatures around 5000 K, pressures of roughly 1000 atm, and heatingand cooling rates above 10¹⁰ K/s (K. S. Suslick, Science, Vol. 247, 23Mar. 1990, pgs. 1439-1445). These high temperatures and pressures cancreate extreme physical and chemical conditions in otherwise coldliquids.

The following sonochemical effects can be observed in chemical reactionsand processes: increase in reaction output and speed, changing ofreaction pathway and increase in the reactivity of reagents orcatalysts, improvement of phase transfer and activation catalysts,avoidance of catalysts and breakage molecular bonds, improvement ofparticle and droplets formations and synthesis.

Common for sonochemical reactions and processes is that, for thecreation of cavitation bubbles in a liquid, application of ultrasonicoscillations on the liquid is used. The basic equipment which is used insonochemistry appears as ultrasonic devices of various designs.

This method of conducting sonochemical reactions is sufficientlyeffective for processing small volumes of liquids and has found itschief application on the level of laboratory research. Transitioning tolarge scale volumes, however, which are used in industry, issignificantly difficult and even at times impossible. This is associatedwith the problems which arise during the scaling up of cavitation thatis produced with the aid of ultrasonic oscillations.

It is possible to avoid these shortcomings, however, by producing thequality of the initiator of sonochemical reactions, cavitation bubbles,through the course of hydrodynamics. An example of using hydrodynamiccavitation for conducting sonochemical reactions is presented in thework of: Pandit A. B., Moholkar V. S., “Harness Cavitation to ImproveProcessing,” Chemical Engineering Progress, July 1996, pgs. 57-69.

Methods disclosed in U.S. Pat. Nos. 5,937,906; 6,012,492 and 6,035,897,for conducting sonochemical reactions and processes using in largescales liquid medium volumes, involve passing a hydrodynamic liquid flowat a velocity through a flow through channel internally containing atleast one element to produce a local constriction of the hydrodynamicliquid flow. The velocity of the liquid flow in the local constrictionis at least 16 msec. A hydrodynamic cavitation cavern is createddownstream of the local constriction, thereby generating cavitationbubbles. The cavitation bubbles are shifted with the liquid flow to anoutlet from the flow through channel and the static pressure of theliquid flow is increased to at least 12 psi. The cavitation bubbles arethen collapsed in the elevated static pressure zone, thereby initiatingthe sonochemical reactions and processes.

The existing methods are not sufficient to generate significantcompression energy release during bubble collapse.

The compression of the bubbles during cavitation in the discoursepatents occurs under static pressure P₁ increased in the liquid flow.Increasing static pressure of the liquid flow is a linear process andpressure cannot be higher than P₁>0.3 P (to avoiding cavitationsuppression), where P is the static pressure before local constrictionwhich passes a hydrodynamic liquid flow through a flow-through localconstriction, and P₁ is the static pressure behind local constriction.In most cases cavitation bubbles collapse when static pressuresurrounding the bubble is P₁=(0.05-0.1) P.

The power output, N, from the cavitation bubble collapse is

${N = {4.60\mspace{11mu} R^{2}\sqrt{\frac{P_{1}^{2}}{\rho}}}},$where R—maximum radius the bubble has at the beginning of collapse,P₁—is hydrostatic external pressure surrounding the bubble, ρ—liquiddensity.

There are different approaches to account for the shockwave producedfrom a cavity collapse to, but an approximate relationship for thepressure peak amplitude, p_(p), given by Brennan is p_(p)=100 RP₁/r,where R—is the maximum bubble radius, r—is the distance from the bubble,and P¹⁻ is hydrostatic external pressure surrounding the bubble. (C. E.Brennan. Cavitation and Bubble Dynamics. Oxford University: New York,1995.)

Thus, utilization of static pressure P₁ in the liquid flow forcompression of the bubbles is not an effective method and leads to a lowintensity of sonochemical reactions and decrease the degree of heatingthe medium. Accordingly, there is a continuing need for alternativemethods for realizing sonochemical reactions which can provide moreeffective utilization energy of the hydrodynamic flow. The presentinvention contemplates a new and improved method for conductingsonochemical reactions and processes and allows the utilization of moreeffective hydrodynamic cavitation regimes.

SUMMARY

Described herein are methods for conducting sonochemical reactions andprocesses in a liquid. In one embodiment, a method for conductingsonochemical reactions and processes can include passing a liquid atstatic pressure (P) through a constriction of a device to form a liquidjet having cavitation bubbles contained therein, wherein the cavitationbubbles are formed as the liquid passes through the constriction. Thecavitation bubbles in the liquid jet are then subjected to a compressivestagnation pressure, P_(st), wherein P_(st) is in the range ofP_(st)=(0.5−0.99)*P, by colliding the cavitation bubbles with a targetwithin less than 1 millisecond or less than 0.5 millisecond of theliquid exiting the constriction.

The constriction can be at least one orifice, nozzle or aperturesuitable for forming cavitation bubbles in a liquid. The constrictioncan be arranged in the device such that the constriction isperpendicular to the inlet flow of the liquid into the device. Inanother embodiment, the constriction can be arranged in the device suchthat the constriction is parallel to the inlet flow of the liquid intothe device.

The method for conducting sonochemical reactions and processes in aliquid can be carried out by passing the liquid through the device inone or multiple passes, such as two or more passes through the device.The liquid can be passed through the device at an inlet static pressure(P) of at least 250 or 500 psi.

In one embodiment, the compressive stagnation pressure, P_(st),resulting from colliding the cavitation bubbles with a target withinless than 1 millisecond of the liquid exiting the constriction can bedefined as being greater than 0.55*P and less than 0.85*P.

In another embodiment, the target can be an impact body. The impact bodycan be positioned in the device downstream of the constriction such thatthe impact body is between 4 to 200 mm from the outlet of theconstriction. The impact body can have an impact surface for thecolliding cavitation bubbles, for example, the impact surface can beperpendicular to the inlet flow of the liquid into the device or theliquid jet exiting the constriction.

The target can also be a second liquid jet. The second liquid jet cancontain cavitation bubbles. For example, the cavitation bubbles in thesecond liquid jet in the device can be formed by passing a liquid or aportion of the liquid entering the device through a second constriction.The second constriction can be perpendicular to the inlet flow of theliquid into the device.

The liquid being passed through the device can be an aqueous liquid,organic liquid or a mixture thereof. In one embodiment, the liquidentering the device can contain at least one gas or gaseous component,such as a dissolved or entrained gas in the liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates one embodiment of a cavitation device 10 that can beused for conducting sonochemical reactions and processes. A longitudinalcross-sectional view of the device 10 is shown.

FIG. 2 illustrates one embodiment of a cavitation device 20 that can beused for conducting sonochemical reactions and processes. A longitudinalcross-sectional view of the device 20 is shown.

DETAILED DESCRIPTION

Herein, when a range such as 5-25 (or 5 to 25) is given, this meanspreferably at least or more than 5 and, separately and independently,preferably not more than or less than 25. In an example, such a rangedefines independently not less than 5, and separately and independently,not more than 25.

A method has been discovered for an efficient for conductingsonochemical reactions and processes by subjecting cavitation bubbles toa compressive stagnation pressure upon colliding with a target. It hasbeen found that selective use of a target in a cavitation device canimprove the sonochemical efficiency when cavitation bubbles in a liquidstream are collided with the target less than 1 millisecond uponformation from a constriction to impart a compressive stagnationpressure of 50 to 99 percent of the static pressure of the liquidentering the constriction. The cavitation bubbles are collapsed uponcolliding with the target and abrupt and forceful energy releasebeneficially increases the efficiency of sonochemical reactions andprocesses in an unexpected manner.

Referring now to the drawings wherein the showings are for purposes ofillustrating various embodiments of the present invention only and notfor purposes of limiting the same.

FIG. 1 shows a device 10 for conducting sonochemical reactions andprocesses in a liquid. The device 10 includes a liquid inlet 2 witharrow A indicating the direction of liquid flow into the inlet 2. At theopposite end of the device, a liquid outlet 3 is shown with an arrowindicating the direction of liquid flow out of the outlet 3. The liquidflow path through the device 10, e.g., through the inlet 2 and outlet 3,is defined by a channel 8, which can be a tube or pipe having a circularcross-section.

The liquid can be passed through the device 10 with fluid pumpingdevices as known in the art, such as a pump, centrifugal pump,positive-displacement pump or diaphragm pump. An auxiliary pump canprovide liquid flow under pressure to the device, i.e. processingpressure. The processing pressure is preferably at least 200, 400, 600,800, 1000, 2000 or 3000 psi.

The device 10 can include a constriction or flow constriction. Theconstriction can be an orifice, baffle, bluff body or nozzle.Preferably, the constriction is fixed in the device such that is staticduring the formation of a liquid jet containing cavitation bubbles. Theorifice can be any shape, for example, cylindrical, conical, oval,right-angled, square, etc. Depending on the shape of the orifice, thisdetermines the shape of the liquid jets containing cavitation bubblesflowing from the flow constriction. In certain embodiments, the orificecan be configured in the shape of a Venturi tube, aperture, nozzle,orifice of any desired shape, or slot. The orifice can have anydiameter, for example, the diameter can be greater than 0.1, 0.3, 0.5,0.7, 1, 2, 3, 5, 10 mm or more, and preferably more than 0.3 mm. In oneexample, the diameter of the orifice can be less than 2, 1 or 0.5 mm.

The liquid enters the constriction at a static pressure, P. The staticpressure, P, can be at least 200, 300, 400, 500, 600, 700, 800, 900,1000, 2000, 3000, 4000, 5000, 10000, 20000, 30000 psi and higher. As theliquid passes through the constriction, a liquid jet is formed havingcavitation bubbles formed therein. The liquid jet exiting theconstriction has an increased velocity, for example, the liquid jet canhave a velocity of 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500meters/second and higher.

As shown, the device 10 includes a circular orifice opening 5 formed byplate 4 for generating and forming a liquid jet containing cavitationbubbles as the liquid entering the device travels through the orifice.It will be appreciated that the plate 4 can be embodied as a disk whenthe constriction 5 has a circular cross-section, or the plate 4 can beembodied in a variety of shapes and configurations that can match thecross-section of the constriction 5. The liquid jet exits theconstriction 5 can travels through the device and collides with atarget, for example, an impact target 6. An impact target 6 can be asolid body arranged in the device 10 in the flow path, either the entireor partial flow path, of the liquid jet. The impact target 6 can containan impact surface, e.g., 6 a, for contacting the cavitation bubblescolliding with the target. Preferably, the impact surface 6 a has alarger surface area than the cross-sectional area of the constriction 5opening as shown in FIG. 1.

The impact target 6 is positioned downstream from the constriction 5 inthe device 10. Preferably, there are no objects positioned in thechannel 8 or other constrictions arranged between the constriction 5exit and the impact surface 6 a. The impact surface 6 a can bepositioned in the channel 8 of the device 10 such that the surface isperpendicular to the direction of the liquid flowing into the device 10upstream of the constriction 5. Alternatively, the impact surface can bepositioned parallel or at an angle (e.g., 30, 45, 60°) to the directionof the liquid flowing into the device 10 upstream of the constriction 5.The impact surface or impact body can be spaced away from and downstreamof the constriction exit at a distance in the range of 4 to 200 mm, 10to 150 mm, 25 to 100 mm or 40 to 80 mm.

In one embodiment, the impact surface 6 a is positioned away from anddownstream of the constriction exit such that the liquid jet containingcavitation bubbles exiting and being formed by passage through theconstriction takes less than 1 millisecond to reach and collide with theimpact surface. Alternatively, the liquid jet containing cavitationbubbles takes less than 0.8, 0.7, 0.6, 0.5 or 0.4 millisecond to reachthe impact surface after exiting the constriction as described above.

In operation, a hydrodynamic liquid stream or processing liquid movesalong the direction, indicated by arrow A, through the inlet 2 and flowsinto flow-through channel 8. As the liquid stream approaches theconstriction 5, static pressure P applied by a pump to the liquid forcesit through the constriction 5 in a liquid jet through the constriction5. A liquid jet containing exits the constriction with cavitationbubbles being formed therein and travels downstream with no obstructionsbefore impacting target 6 within 1 milliseconds or less of exiting theconstriction 5. Upon collision with the target (e.g., impact surface 6a), a compressive stagnation pressure P_(st)=(0.5−0.99)×P develops atthe jet impact compression point 7 at or near the impact surface 6 athat forces the collapse of one or more of the cavitation bubbles in theliquid jet.

The power output, N, of the forced collapse of a cavitation bubble, forexample in the liquid jet, can be measured as

${N = {4.60R^{2}\sqrt{\frac{P_{st}^{3}}{\rho}}}},$where R is the initial radius of the bubble at the beginning ofcollapse, P_(st) is the compressive stagnation pressure surrounding thebubble, ρ is the density of the liquid surrounding the bubble. Shockwavepressure peak amplitude of the collapse of the cavitation bubble can bemeasured as p_(p)=100 R*P_(st)/r, wherein r is the distance from thecenter of the bubble to the surface of the impact body.

In one embodiment, the cavitation bubbles moving into the impactcompression zone or point 7 within 1 millisecond or less of the liquidjet exiting the constriction 5 can maintain bubble size (initial radiusR) as the bubbles travel from the constriction exit to the impactsurface before collapse. In general, cavitation bubbles travelingdownstream of a constriction will reduce in size and collapse underdownstream pressure. In the present disclosure, the short time periodbetween cavitation bubble formation and collapse thereof by impact withthe target allows for the utilization of more effective hydrodynamiccavitation regimes for conducting sonochemical reactions and processeswithout the cavitation bubble significantly reducing in size andcollapsing under downstream pressure. The increased bubble radius uponcollapse in the present disclosure provides a higher power output uponcollapse as compared to a cavitation bubble collapsing under downstreampressure without impacting a target.

The methods described herein make it possible to process liquids withincreased viscosity, such as viscous liquids and heavy oils. Collapsinga cavitation bubble in water requires less collapsing pressure due, inpart, to the high surface tension of water, low viscosity, and a highdegree of gas solubility. In contrast, the collapse of a cavitationbubble in organic liquids and high molecular weight liquids such as,monomers, polymers, oligomers, petrochemicals, hydrocarbons and resinscan be difficult because the liquids have high viscosities and low gassolubility. The proposed method of processing liquid media can be usedto produce systems comprising polymers, oligomers, monomers,petrochemicals, hydrocarbons, resin or a combination of any of these,loaded or not loaded with a filler material. Filler material meansfiller particles, filler droplets, or fillers in any form, which can beorganic or inorganic, conductive or non-conductive.

FIG. 2 shows another embodiment of a device suitable for carrying outthe methods discussed herein. The device 20 includes a channel 11defining an inlet 12 with arrow A indicating the direction of liquidflow into the inlet 12 and, at the opposite end of the device, an outlet16 is shown with an arrow indicating the direction of liquid flow out ofthe outlet 16. The channel 11 can be a flow-through channel, which canbe a tube or pipe having a circular cross-section openings. The liquidentering the device 20 can be supplied as discussed for device 10 ofFIG. 1, for example, by a pump at a desired liquid static pressure, P.

The liquid entering the device 20 through inlet 12 is split into twostreams indicated by arrows B as it flows around an upstream portion ofbody 18. Body 18 is arranged in channel 11 and can contain at least oneconstriction. The constriction can be an orifice, baffle, bluff body ornozzle. Preferably, the constriction is fixed in the device such that itis static during the formation of a liquid jet containing cavitationbubbles. The orifice can be any shape, for example, cylindrical,conical, oval, right-angled, square, etc. Depending on the shape of theorifice, this determines the shape of the liquid jets containingcavitation bubbles flowing from the flow constriction. In certainembodiments, the orifice can be configured in the shape of a Venturitube, aperture, nozzle, orifice of any desired shape, or slot. Theorifice can have any diameter, for example, the diameter can be greaterthan 0.1, 0.3, 0.5, 0.7, 1, 2, 3, 5, or 10 mm, and preferably more than3 mm. In one example, the diameter of the orifice can be less than 2, 1or 0.5 mm.

As shown, body 18 contains two constrictions, e.g., a first constriction13 a and a second constriction 13 b. The constrictions 13 a, 13 b shownin FIG. 2 are arranged such that the liquid flows through theconstrictions into passageway 15 in a direction perpendicular to thedirection of liquid flow entering the device 20 through inlet 12. Toguide the liquid flow, the constrictions 13 a, 13 b are also arrangedperpendicular to the direction of liquid flow entering the device 20through inlet 12. For instance, the openings in the constrictions facethe inner wall of the of the flow channel 11. The passageway 15 of body18 is open to the downstream outlet 16 of the device 20 such that theliquid flowing through the constrictions 13 a, 13 b can exit the device.

A portion of the liquid entering the device 20 flows into constriction13 a at a static pressure, P, which can be as discussed above forconstriction 5. As the liquid flows through and exits the firstconstriction 13 a, a liquid jet containing cavitation bubbles is formed.The liquid jet containing cavitation bubbles exits the firstconstriction 13 a and travels into the passageway 15 of body 18. In asimilar manner, a portion of the liquid entering the device 20 flowsinto constriction 13 b at a static pressure, P, wherein the staticpressure at constriction 13 b can be the same as the static pressure atconstriction 13 a. As the liquid flows through and exits the secondconstriction 13 b, a liquid jet containing cavitation bubbles is formed.As arranged in the device 20, the first and second constrictions opposeone another and their respective openings are in alignment or inregister (e.g., vertically as shown) with one another. During operation,the liquid jet containing cavitation bubbles (i.e. first liquid jet)exiting the first constriction 13 a collides with the liquid jetcontaining cavitation bubble (i.e. second liquid jet) exiting the secondconstriction 13 b at impact compression point 14 at compressivestagnation pressure P_(st). The second liquid jet, or alternatively thefirst liquid jet, acts as an impact target to facilitate the collapse ofthe cavitation bubbles contained in both streams. Upon collapse of thecavitation bubbles from the first and second liquid jets, the liquidexits the device 20 through outlet 16.

The first and second constrictions 13 a, 13 b are spaced apart from oneanother, for example, in the range of 4 to 200 mm, 10 to 150 mm, 25 to100 mm or 40 to 80 mm. The constrictions 13 a, 13 b are positioned awayfrom each other such that the liquid jets containing cavitation bubblesand being formed by passage through the constrictions take less than 1millisecond to reach and collide with one another. Alternatively, eitherliquid jet containing cavitation bubbles can take less than 0.8, 0.7,0.6, 0.5 or 0.4 millisecond to collide with the other liquid jetcontaining cavitation bubbles, e.g., the liquid jet exiting the oppositeconstriction.

For device 20, the compressive stagnation pressure upon collisionbetween the two liquid jets can be P_(st)=(0.5−0.99)×P at the jet impactcompression point 14 that forces the collapse of one or more of thecavitation bubbles in the liquid jets. The power output, N, of thecollision and the shockwave pressure peak amplitude, p_(p), can bemeasured for the collision of the two liquid jets as described above forliquid jet in device 10.

As used herein, the liquid utilized in the methods and devices describedherein can be any suitable liquid. For example, the processing liquidcan be an aqueous or non-aqueous liquid or organic liquid. The organicliquid can include low and high molecular weight liquids or componentssuch as, monomers, polymers, oligomers, petrochemicals, hydrocarbons andresins. Also as used herein, petrochemicals and hydrocarbons are usedinterchangeably and refer to any petroleum or hydrocarbon mixture suchas crude oil, used motor oil, vacuum gas oils, refining residuum, catcracker bottoms, fuel oil, vacuum tower bottoms, atmospheric towerrefining bottoms, residual fuel oils and mixtures thereof.

As used herein, polymers, oligomers, monomers, resin are usedinterchangeably and refer to any material include epoxies, maleimides(including bismaleimide), acrylates and methacrylates, and cyanateesters, vinyl ethers, thiol-enes, fumarates and maleates. Otherexemplary compounds include polyamides, phenoxy compounds, benzoxazines,polybenzoxazines, polyether sulfones, polyimides, siliconized olefins,polyolefins, polyesters, polystyrenes, polycarbonates, polypropylenes,poly(vinyl chloride)s, polyisobutylenes, polyacrylonitriles, poly(vinylacetate)s, poly(2-vinylpyridine)s, cis-1,4-polyisoprenes,3,4-polychloroprenes, vinyl copolymers, poly(ethylene oxide)s,poly(ethylene glycol)s, polyformaldehydes, polyacetaldehydes,poly(b-propiolacetone)s, poly(10-decanoate)s, poly(ethyleneterephthalate)s, polycaprolactams, poly (11-undecanoamide)s,poly(m-phenylene-terephthalamide)s,poly(tetramethlyene-m-benzenesulfonamide)s, polyester polyarylates,poly(phenylene oxide)s, poly(phenylene sulfide)s, poly(sulfone)s,polyetherketones, polyetherimides, fluorinated polyimides, polyimidesiloxanes, poly-isoindolo-quinazolinediones, polythioetherimidepoly-phenyl-quinoxalines, polyquinixalones, imide-aryl etherphenylquinoxaline copolymers, polyquinoxalines, polybenzimidazoles,polybenzoxazoles, polynorbornenes, poly(arylene ethers), polysilanes,parylenes, benzocyclobutenes, hydroxyl-(benzoxazole) copolymers,poly(silarylene siloxanes), bisphenol, naphthalene, phenol or cresolnovolac, dicyclopentadiene, polybutadiene, polycarbonate, polyurethane,polyether, or polyester, poly(butadienes), poly(carbonates),poly(urethanes), poly(ethers), poly(esters), simple hydrocarbons, andsimple hydrocarbons containing functionalities such as carbonyl,carboxyl, amide, carbamate, urea, ester, poly(butadienes),poly(carbonates), poly(urethanes), poly(ethers), poly(esters) or ether.

The liquid can be comprised of a mixture of two or more liquidcomponents such as one liquid soluble in one of the components as wellas mutually insoluble liquids, for example, in the form of emulsions.Furthermore, the processing liquid can include dense or non-liquidcomponents, for example filler material particles, such as particlesthat exhibit the characteristics of a solid, semisolid or a highviscosity liquid, which can be present as a reactant, filler or performsthe function of a catalyst. There may also be particles of several solidcomponents present in the liquid flow. There may also be at least onegaseous component present in the liquid flow.

In order to promote a further understanding of the invention, thefollowing examples are provided. These examples are shown by way ofillustration and not limitation.

Example 1

A potassium iodide solution (KI solution) having a concentration of 1weight percent in distilled water was prepared. Two single-orificedevices similar to that shown in FIG. 1 were used to process the KIsolution. The first device contained a constriction orifice having anopening of 1.85 mm and the second device contained a constrictionorifice having an opening of 0.35 mm. The KI solution was processedthrough each device for 20 minutes that included repeated circulationthrough the devices.

The iodine concentration was measured after processing to quantify thesonochemical efficiency. The concentration of I₃− ion (based on Weisslerreaction) was measured at an absorption wavelength of 355 nm by using aspectrophotometer. The Weissler reaction in which iodide is oxidized toa triiodide complex (I₃ ⁻) has been widely used for measurement of theintensity of ultrasonic and hydrodynamic cavitation.

Table 1 below shows the operating conditions for each device duringprocessing of the KI solution. P is the static pressure at the inlet ofthe constriction and P_(st) is the compressive stagnation pressurecalculated as described above and measured at the collision of theliquid jet with the impact body. T is the time between the liquid jetexiting the constriction orifice and the liquid jet colliding with theimpact body positioned downstream of the constriction orifice.

TABLE 1 Orifice size, P, P_(st), T, Iodine concentration, mm PSI PSIP_(st)/P millisecond micromole/l 1.85 500 79 0.16 2.76 1.6 1.85 1000 1430.14 1.32 2.3 1.85 500 290 0.58 0.50 16.5 1.85 1000 540 0.54 0.26 19.30.35 4000 2880 0.72 0.024 54.1 0.35 8000 6400 0.80 0.018 81.6

Hydrodynamic cavitation had a maximum efficiency of about 1.65×10⁻⁵−8.16×10⁻⁵ moles of I₃ ⁻ per liter when the compressive stagnationpressure was in range of P_(st)=(0.5-0.99)*P as compared with themaximum of almost 2.3×10⁻⁶ mol 1⁻¹ for a compressive stagnation pressureof P_(st)=0.14*P.

The utilization of devices as shown herein and of certain compressivestagnation pressures in the liquid flow for compression and collapse ofcavitation bubbles is an effective method and leads to a high intensityof sonochemical reactions and increases the degree of heating in themedium. Methods described herein can increase the rate of chemicalreactions, cause reactions to occur under less restrictive conditions,reduce the number of steps required in a reaction, and enhance catalystefficiency or initiate of reduction at carbon-carbon bonds.

Examples of sonochemical reactions that can be improved of using themethods described herein are preparation of high purity materials,narrow size distributions of nanoparticles and emulsions with uniformshapes, improvement of the performance of phase transfer catalysts andreactivity of catalysts or reagents, degassing of liquids and hydrolysisof non-hydratable phospholipids in oil, promoting conversion ofdissolved calcium and bicarbonate ions into calcium carbonate andmicrobial cell disruption, treatment of liquid hydrocarbon such as crudeoil, fuel oil, bitumen, and various bio-fuels, reduction in viscosityand increases in both yield and temperature of such hydrocarbons, andproducing a filled resin electrically and thermally conductivematerials.

In another example, the present disclosure relates to reactions andprocesses which are effective and useful in the fields of chemistry,electronic materials, biochemistry, agriculture, medication, andpharmaceutical industry.

It should now be apparent that there has been provided, in accordancewith the present invention, a novel process for enhancing alcoholproduction by utilizing conventional starch by-products that satisfiesthe benefits and advantages set forth above. Moreover, it will beapparent to those skilled in the art that many modifications,variations, substitutions and equivalents for the features describedabove may be effected without departing from the spirit and scope of theinvention. Accordingly, it is expressly intended that all suchmodifications, variations, substitutions and equivalents which fallwithin the spirit and scope of the invention as defined in the appendedclaims to be embraced thereby.

The preferred embodiments have been described, herein. It will beapparent to those skilled in the art that the above methods mayincorporate changes and modifications without departing from the generalscope of this invention. It is intended to include all suchmodifications and alterations in so far as they come within the scope ofthe appended claims or the equivalents thereof.

What is claimed is:
 1. A method of conducting sonochemical reactions or processes in a liquid comprising the steps of: a. passing a liquid at static pressure P through a constriction of a device to form a liquid jet containing cavitation bubbles; and b. subjecting the cavitation bubbles in the liquid jet to a compressive stagnation pressure, P_(st), wherein P_(st) is P_(st)=(0.5−0.99)P, by colliding the cavitation bubbles with a target within less than 1 millisecond of the liquid exiting the constriction.
 2. The method of claim 1, the cavitation bubbles colliding with the target within less than 0.5 millisecond of the liquid exiting the constriction.
 3. The method of claim 1, the constriction being perpendicular to the inlet flow of the liquid into the device.
 4. The method of claim 1, the constriction being parallel to the inlet flow of the liquid into the device.
 5. The method of claim 1, the target being an impact body.
 6. The method of claim 5, the impact body being positioned in the device downstream of the constriction such that the impact body is between 4 to 200 mm from the outlet of the constriction.
 7. The method of claim 5, the impact body having an impact surface for the colliding cavitation bubbles, the impact surface being perpendicular to the inlet flow of the liquid into the device.
 8. The method of claim 1, the target being a second liquid jet.
 9. The method of claim 8, the second liquid jet containing cavitation bubbles.
 10. The method of claim 9, the second liquid jet being formed by passing a portion of the liquid through a second constriction in the device.
 11. The method of claim 9, the second constriction being perpendicular to the inlet flow of the liquid into the device.
 12. The method of claim 1, the liquid being an aqueous liquid, organic liquid or a mixture thereof.
 13. The method of claim 1, the liquid jet containing cavitation bubbles comprising at least one solid, semisolid, particulate or a mixture thereof.
 14. The method of claim 1, the liquid comprising at least one gaseous component.
 15. The method of claim 1, the constriction comprising at least one orifice, nozzle or aperture.
 16. The method of claim 1, the method being carried out in one pass through the constriction of the device.
 17. The method of claim 1, the method being carried out in two or more passes through the constriction of the device.
 18. The method of claim 1, the static pressure P being greater than 250 psi.
 19. The method of claim 1, the static pressure P being greater than 500 psi.
 20. The method of claim 1, P_(st) being greater than 0.55*P and less than 0.85*P. 